lemans24 Easiest thing is to call Tom at Kirkham and see what thermostat is in the motor. It may be a 160f. Which would put you in the 140f numbers at highway speeds over 50 mph. Your gauge could also not be correct or calibrated either. Mine are about 10-15 degrees off when running. Are your gauges mechanical or electric with sensors?
The other idea is to add a small strip of cardboard to the radiator and drive the car. See how much changes the temp on the highway.
Unless the motor is really driving ugly, leave it alone and enjoy.
Rick L.